Particle motion or transport in suspensions and colloids is important in many applications including drug delivery, disinfection, filtration and fluid sample analysis. Several mechanisms exist to induce directed motion of colloidal particles, such as employment of one or more external forces. External forces can include electrostatic, dielectric, magnetic, acoustic, optical and/or inertial effects. Effective application of external forces can necessitate apparatus of complex architecture and design. Additionally, use of external forces often fails to reveal meaningful information of particle systems, such as zeta potential and particle size.